A common type of home swimming pool construction, widely employed because of lower cost, involves forming an opening in the ground and lining the opening with a sheet of plastic such as a vinyl plastic. In this type of construction, as distinguished from the so-called gunnite construction wherein a fluid concrete is sprayed over a steel reinforcing web, it is neither convenient nor economically practical to provide the pool with built in steps for entry and exit. Accordingly, some type of ladder is generally employed for pool entry. It is known, as shown in U.S. Pat. Nos. 3,236,012 to Laven, 3,755,981 to West and 3,848,378 to Witte, for example, to provide stairs for such vinyl lined swimming pools, extending upward and outward from the side of the pool. These structures use complex and costly arrangements for anchoring the steps to the earth surrounding the pool structure and for connecting and sealing the step construction to the pool structure itself.
In conventional gunnite type swimming pools there is increasingly wide application of built-in therapy pools. A laterally extending basin area is formed integrally with the pool and separated therefrom by a divider that extends to a point just below the water level surface so as to provide a limited water communication between the therapy area and the main body of the pool. Various arrangements have been provided to enable selective control of the normal water recirculation and heating for the main pool body and for the therapy area, typical apparatus of this type being shown in U.S. Pat. Nos. 3,623,165 to Whittell, Jr., 3,781,925 to Curtis et al., and 3,801,992 to Sable. Such therapy basins have not heretofore been available for the less expensive plastic lined swimming pools and, moreover, have required structures that limit the use of the therapy area by permanently separating this area from the main body of the pool.
Accordingly, it is an object of the present invention to provide a single structure that affords an inexpensive solution to the above-mentioned problems of both entry and therapy basins.